A brushless motor comprises a stator and a rotor rotatably mounted to the stator. The stator comprises a stator core comprising inwardly extending teeth and windings wound about the teeth. The rotor comprises a shaft rotatably supported by the stator, a rotor core fixed to the shaft and magnets fixed to the rotor core.
Traditional brushless motors used in industry have a wide opening to the slot between the teeth of the stator and a small air-gap between the rotor and the stator, which results in a large cogging torque and therefore great vibration and noise. This is especially noticeable when the motor is used in a high speed application such as a bladeless fan.
Therefore, there is a desire to develop an improved brushless motor with reduced cogging torque to thereby reduce vibration and noise of the motor.